Patent GB-790587-A (GB)
Title: Improvements in the production of 1-aminobenzophenone-sulphone-2-aldehydes or -ketones
Filed: 1956-04-09
Abstract: The invention comprises 1-amino-benzo-phenone - sulphone - 2 - aldehydes or ketones of the formula: <FORM:0790587/IV (b)/1> in which R is hydrogen or alkyl, aralkyl, aryl, or cycloalkyl, and substituents other than those shown (e.g. alkyl, halogen, nitro, alkylsulphonyl) may be present.  They are made by nitrating benzophenone-sulphones substituted by -CH2R in 2-position to give the corresponding 1-nitro-benzophenone-sulphones, converting these to the corresponding isoxazoles, and reducing the latter in an acid medium. The starting materials may be dinitrated-in 1-position and another position.  Conversion to the isoxazoles may be effected with oleum of 60-65 per cent sulphur trioxide content, and ferrous sulphate may be used to reduce the isoxazoles.  The products are dyestuff intermediates and themselves dye cellulose acetate, nylon, polyurethane, and polyester fibres.  In examples: (1) 2-methyl- and 2-ethyl-benzophenone-sulphone are each nitrated (using potassium nitrate and sulphuric acid), the 1-nitro bodies are converted to the isoxazoles with oleum, and the isoxazoles are each reduced with ferrous sulphate in sulphuric acid to give 1 - aminobenzophenone - sulphone - 2 - aldehyde and 1-amino-2-acetyl-benzophenone sulphone; (2) 1 - nitro - 2 - methylbenzophenone sulphone, obtained as under (1), is further nitrated to give two dinitro bodies which are separated and separately ringclosed to the isoxazoles and reduced with ferrous sulphate and sulphuric acid to give two different nitro 1-amino-benzophenone-sulphone-2-aldehydes.ALSO:The invention comprises 1-amino-benzo-phenone-sulphone-2-aldehydes or ketones of the formula: <FORM:0790587/IV (b)/1> in which R is hydrogen or alkyl, aralkyl, aryl, or cycloalkyl, and substituents other than those shown (e.g. alkyl, halogen, nitro, alkyl-sulphony) may be present.  They are made by nitrating benzophenone-sulphones substituted by -CH2R in 2-position to give the corresponding 1-nitro-benzophenone-sulphones, converting these to the corresponding isoxazoles, and reducing the latter in an acid medium.  The starting material may be dinitrated in 1-position and another position.  Conversion to the isoxazoles may be effected with oleum of 60-65 per cent sulphur trioxide content, and ferrous sulphate may be used to reduce the isoxazoles.  The products dye cellulose acetate, nylon, polyurethane, and polyester fibres.  In examples: (1) 2-methyl- and 2-ethyl-benzo-phenone-sulphone are each nitrated (using potassium nitrate and sulphuric acid), the 1-nitro bodies are converted to the isoxazoles with oleum, and the isoxazoles are each reduced with ferrous sulphate in sulphuric acid to give 1 - aminobenzophenone - sulphone - 2 - aldehyde and 1 - amino - 2 - acetyl - benzophenone sulphone; (2) 1-nitro-2-methyl-benzophenone sulphone, obtained as under (1), is further nitrated to give two dinitro bodies which are separated and separately ring-closed to the isoxazoles and reduced with ferrous sulphate and sulphuric acid to give two different nitro-1-amino-benzophenone-sulphone-2-aldehydes.